Field of the Invention
The present invention relates to a novel promoter, and more particularly, to a light-inducible promoter and a gene expression system containing the same.
Background of Technique
In recent years, the efforts to analyze nucleotide sequences of genes are proceeding together with the attempts to use microalgae in the latest biotechnology including the development of biofuel, reduction in carbon dioxide generation, and production of high value-added materials. As part of these efforts, the attempts to introduce useful genes into existing microalgae to express desired traits have been continuing. However, microalgae have problems in view of the transgenic technology, such as low transformation efficiency and low expression efficiency of introduced genes (Lumbreras et al., Plnat J. 1998; 14: 441-447).
As one of the important schemes to solve the problems, various kinds of promoters for microalgae have been developed, and the use of promoters derived from the microalgae could induce effective transformation and gene expression when compared with the use of known promoters for higher plants (Walker et al., J. Applied Phycol. 2005; 17: 363-368). As a result, the promoters for Chlamydomonas (Schroda et al., The Plant Journal 2000; 21(2): 121-131) and Dunaliella (Li et al., Mol Biol. Rep. 2010; 37: 1143-1154) have been recently researched and presented.
The promoter derived from Chlamydomonas reported by Schroda et al. is prepared by fusing two different promoters, and induces gene expression mainly by thermal shock. In the case where the promoter is used, the application of heat for the introduction of gene expression may burden the growth or metabolic processes of algae.
The promoter derived from Dunaliella reported by Li et al. induces the expression of genes in the high salinity conditions (2M NaCl). Since the promoter can be applied to only halophilic species, the range of application thereof is narrow.
Therefore, the development of promoters which are applicable to various organisms and thus have a wide range of application, do not burden the growth or metabolic processes of organisms, and can conveniently regulate the expression of genes is urgent.
Throughout the entire specification, many papers and patent documents are referenced and their citations are represented. The disclosures of cited papers and patent documents are entirely incorporated by reference into the present specification, and the level of the technical field within which the present invention falls and details of the present invention are explained more clearly.